Why are the HP Prime and HP-35s so unpopular?

[aurelio]

I like particularly Sylvain's and Marco Polo answers, for each job its dedicated tool if available.
I like as Marco the 48's screen and agree when he writes "the 48 screen header, the 48 has better layout, the 7-level stack screen should be optionally rearranged as 5-level with large font, the 50g menu are somewhat confused."
I have no more the prime, i found its keyboard really difficult to read ...
I never had a 35s, it's a nice calculator hestetically but never I bought it , nor used, so no personal experience, but I read quite about its various bugs.
I don't think it's a matter for saying a calculatore is bad or good, it's a matter of taste and usage